Currently I shoot with Nikon 35mm, also with Mamiya 645, (and Nikon DSLR's as well). I love my 645's, but I have had very little luck scanning them with my Epson 4870 Flatbed Scanner (the odd shape of 645 frames is not recognized by the software of my scanner). So, I have opted to stick with 35mm. I like my Nikons but I want that "extra edge" in terms of sharpness. Yes, my nikons are sharp (especially my 180mm 2.8, 80-200mm 2.8, 105mm 2.5, 85mm 1.8, etc) but I guess I am under the impression that Zeiss optics are sharper. After reading the replies on this thread (and I really thank everyone for their input), I wonder if I will be actually getting sharper results with a Zeiss or Leica vs. Nikon? I did look into Hassleblad and it could be an option, especially because my scanner recognizes square format frames. However, I have even less of a clue about the Hassleblad system and would not know where to start!